Folded sheet material and method and apparatus therefor

ABSTRACT

Tissue webs which may be of substantially indefinite length and suitable for cutting to a convenient size for packaging are folded and interfolded. The upper or starter web of the stack is folded in quarters and so arranged that this upper web is readily grasped by the fingers of a hand and easily removed from the stack. The next lower web being interfolded with the upper is partially withdrawn from the stack so that it is presented for easy removal also. Several apparatus arrangements and methods for effecting the folding are described.

United States Patent Nissen et a].

[451 July 25, 1972 [54] FOLDED SHEET MATERIAL AND METHOD AND APPARATUSTHEREFOR Walter D. Nissen, Appleton; Philip G. Hammond, Neenah, both ofWis.

[72] Inventors:

[73] Assignee: Kimberly-Clark Corporation, Neenah,

Wis.

[22] Filed: June 1, 1970 [21] Appl. No.: 42,348

52 u.s.c| ..22l/50,206/57,270/40 51 lnt.Cl ..B65h 1 04 58 FieldofSearch..221 47-5s;270 40;

[56] References Cited UNITED STATES PATENTS 1,256,334 2/1918 Lazar..22l/48 3,401,927 9/1968 Frick et al ..270/40 Primary Examiner-RobertB. Reeves Assistant Examiner-Francis J. Bartuska Attorney-Daniel J.Hanlon, Jr. and Raymond J. Miller ABSTRACT 3 Claims, 23 Drawing FiguresLLL "'I'I'I'A PATENTEDJuL 25 I972 SHEET 1 [IF 4 PATENTEDJUL 25 I972SHEET 2 [IF 4 FIG. 6

FOLDED SHEET MATERIAL AND METHOD AND APPARATUS THEREFOR BACKGROUND OFTHE INVENTION 1. Field of the Invention This invention relates tointerfolded webs and particularly to the starter web for a stack ofinterfolded webs; the invention also relates to apparatus and methodsfor folding a starter web and combining it with other webs of the stack.

2. The Invention With Relation To The Prior Art It is common practice inthe facial tissue field to provide individual tissues interfolded in astack in such manner that withdrawal of the upper tissue web will exposea length of the underlying tissue so that it also may readily be removedfrom the stack. Such tissue stacks are usually retained in a box ofconvenient size for household consumers and such boxes have a windowthrough which the tissues are removed. In the case of interfolded tissueeach upper web, upon its withdrawal by the hand of a user, draws thenext succeeding web through the window to present it for easy removalfrom the stack.

A primary objective of this invention is to so fold an uppermost web ofa stack that it will permit a user to pull on it strongly wheninitiating withdrawals of tissue.

An important object of the invention is to provide a novel folding boardarrangement for achieving the novel fold of the uppermost web of astack.

A further object of the invention is to provide a novel method ofinterfolding webs.

The practice of the invention is of particular importance in connectionwith interfolded tissues and similar webs of relatively low tensile andtear strength. The principles are'applicable to other materials whereinterfolding may be desired as in the packaging of paper toweling,napkins and the like.

Briefly, we have found that starter webs of a stack may be convenientlyfolded to provide four thicknesses of the web. Further, the starter webis folded to permit grasping of the full folded. thickness to providefor withdrawal from a stack without injury to the starting web and thosewebs closely adjacent to it. This arrangement is particularly importantin connection with tightly stacked and boxed webs where considerableresistance to web withdrawal may be present. The starter web for ourpurpose is so folded longitudinally that widthwise quarter folds of theweb are in overlying relation. The starter web also has an openingtowards a side edge of the stack but is closed along a longitudinal zoneintermediate side edges of the stack. The next lower web of the stackhas a fold lying in the opening of the uppermost web so that it will bepartially withdrawn from the stack when the uppermost web is pulledfree. By providing the starter web folded along the intermediate zone,the four thicknesses of web may be readily grasped by the fingers of auser.

The four folds are suitably made by first folding the traveling web intohalves longitudinally of the web. This half folded web is then againfolded to provide the quarter folds and is simultaneously interfoldedwith the next lower web of the stack. This latter web is itselfconveniently generally folded as described in US. Pat. No. 3,401,927, R.H. Frick, inventor, and assigned to the same assignee as the presentinvention.

The folding device of this invention includes two successivelypositioned folding boards. A first is for the purpose of half foldingthe uppermost web of the stack and the second for interfolding the firstweb with a second while completing the fold of the first web intoquarter folds. The second folding board may be similar to the foldingboard shown in FIG. 6 of the above-mentioned Frick patent and may bethreaded in substantially the same manner as the sheet illustrated inthat drawing.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more fullyunderstood by reference to the following detailed description andaccompanying drawings which follow. The drawings, for sake of clarity,are somewhat exaggerated in the presentation of folds, fold lines,thicknesses and the like. In the drawings:

FIG. I is a fragmentary view in perspective of a folding mechanism inaccordance with the invention and illustrating the method of folding andinterleaving the two upper webs of a stack;

FIG. 2 is a sectional view taken along line 2-2 of FIG. I illustratingthe relationship of the two upper webs of a stack;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is a fragmentary view illustrating a method of forming the webwhich interleaves with the uppermost web of a stack in accord with theinvention;

FIG. 5 is a view taken along line 55 of FIG. 4;

FIG. 6 is a view taken along line 6-6 of FIG. 4;

FIG. 7 is a fragmentary view like that of FIG. 1 but without the websand with parts broken away illustrating the arrangement of successivefolding boards and associated equipment;

FIG. 8 is a fragmentary view illustrating a method of forming theuppermost web of a stack;

FIG. 9 is a view taken along line 9-9 of FIG. 8;

FIG. 10 is a view taken along line l0-l0 of FIG. 8;

FIG. II is a much enlarged view of the folding mechanism and like thatof FIG. 1 but taken from the rear of the folding boards;

FIGS. .12-18 are sectional views illustrating in detail steps in thefolding of the two uppermost webs of a stack and taken on section linesof FIG. 11, the section lines corresponding in numerals to the numeraldesignating the particular figure of the drawing;

FIG. 19 is a view like that of FIG. 1 but illustrating another method ofinterfolding the upper two webs of a stack in ac- PREFERRED EMBODIMENTSOF THE INVENTION Referring to the drawings and initially particularlyFIGS. 1 to 18 inclusive, the numeral 1 (FIG. I) designates a web whichis to be folded as the uppermost web of a web stack. The numeral 2designates a web which is to be interfolded with web I and to be thenext lower, that is, the second web of the stack.

For the sake of convenience, the folding of web I to the structure ofFIGS. 8, 9 and 10 will first be considered; the folding of web 2 to thestructure of FIGS. 4, 5 and 6 will then be considered separately; andthe formation of the interfolded two webs (FIGS. 1 to 3 and FIGS. 11 to18) will then be described.

The web 1 is directed by suitably positioned guide rolls 3 to a firstfolding board 4 (FIGS. 7 and 8). Board 4 has a first surface 5 in thegeneral form of a trapezoid; a support 6 integral with the-board dependsrearwardly and is adapted for providing support of the board. The boardfurther includes (FIG. 7) a downwardly forwardly directed surface 7 alsoin the general shape of a trapezoid. A web guide rod 8 projectsforwardly beneath and beyond surface 7 angularly to the direction ofsheet travel as indicated by the arrow (FIG. 1) and terminates edges12,13 and forward terminal edge 14 which forms a juncture or corner 15with lateral edge 12. The numeral 16 (FIGS. 7,8) designates a commonjuncture of the board means or of surfaces 5,7 at a narrow zone of theboard 4.

The web 1 is directed under a suitable tension around guides 3 (FIG. 1)and across surface 5. The opposed lateral edge portions of the web areurged downwardly and inwardly of the edges 10,11 of surface 5 (FIGS. 8,11 and 12). Guide 9 (FIGS. 8 and 13) serves further to direct thelateral edge portions of web 1 toward each other. The angular projectingguide rod 8 (FIGS. 8, 14 and 15) urges the lateral edges of web 1further toward each other into overlying relation as the web proceedstoward folding board 17.

Web 2, which is to be folded with web 1, (FIG. 1) is spaced partiallylaterally of and above web 1 as it moves over guide 31 to the rear faceof panel 18 of board 17. Panel 18 (FIG. 4) has an upstanding upperextension mount 19 which may be used to support the board in anyconvenient mount (not shown). This board 17 is similar to the boardshown and described in Frick U.S. Pat. No. 3,401,927 mentioned above butwith limited modifications noted hereinafter. The board is heredescribed sufficiently to indicate its functions in the embodiments ofthis application. Reference may be had to the Frick patent for a moredetailed description. Opposite extension 19 of panel 18 is a lip 20 ofthe board 17. Projecting forwardly from lip 20 in a direction angularlydisposed to the direction of web travel indicated by the arrow (FIG. 1)is a rod 21 providing a folding edge.

The board 17 further includes a panel 22 which projects forwardly ofpanel 18 and upwardly obliquely from horizontally disposed panel 23lying in the direction of web travel. Panel 23 has a slot 24 adapted forreceiving a mounting bolt (not shown). A slot 25 in panel 18 having anedge 27 (FIG. 7) and the edge 26 of panel 23 provide means for effectingfolding of the traveling web 2 (FIG. 4). This slot is of somewhatgreater dimension than the slot shown in Frick U.S. Pat. No. 3,401,927to provide for passage of the folded material and one side iscurvilinear to aid web threading. The board 17 is I suitably of sheetmetal and has bend lines 28,29 (FIG. 7) serving respectively to join thepanels 18,22 and 22,23.

The web 2 itself as it travels on the board 17, conveniently termed aright hand board, is folded to the configuration of FIG. 6.Specifically, the web 2, to achieve this fold (FIG. 6), is passed overguide 31 downwardly along the rear surface of panel 18 (FIGS. 4, 11 and14) and its longitudinal center line crosses the intersection of foldedges 29, 28 and 26. The right hand half (FIG. 4) of the web 2 passesaround the fold edge 28 on the rear side of the board onto the rear faceof the panel 22 (FIG. 15) and makes a turn of 180 on the edge 26 (FIG.4) so as to form the fold 2c (FIG. 6) on the upper surface of panel 26.

The left hand half (FIG. 4) of web 2 forms the folds 2a and 2b (FIG. 6).For this purpose the outer left quarter of web 2 is drawn through slot25 over edge 27 (FIG. 7) while the inner left quarter passes under foldedge or lip (FIG. 7) 20. This inner left quarter is drawn directlythrough the device in the path indicated by the arrow (FIG. 4) to formthe fold 2b; the rod 21 urges the outer quarter over the inner quarterfold 2b to form the fold 2a.

The web 2 is threaded as illustrated in the views of FIGS. 11 and 15with one edge portion passing through slot 25 as shown. The web 1 as itis presented to slot 25 from the surface 7 of board 4 has been largelyfolded upon itself and interfolding of the two webs is initiated as theweb portions pass in the slot (FIG. 15). As illustrated in FIGS. 11 and15 particularly, a first half of an unfolded width of web 2 iscontinuously applied to the traveling web 1 which is folded in halves bythe combined action of board 4 and rod 8. The web 1 is then folded againon itself (FIGS. 15 and 16) into quarters and to interfold web 2. Thisinterfolding is completed as the webs pass under rod 21 in theirmovement in the direction of the arrow (FIG. 1). The completion ofinterfolding is carried out as web 2 is drawn down the rear of panel 22around fold line 29 (FIG. 16) and around edge 26 (FIGS. 17 and 18). Thesecond web 2 has a remaining half width which is folded as illustratedin FIG. 18 beneath folds of the first web and fold portions of itself.

In the embodiment of the folding device or mechanism shown in FIG. 19the resultant interfolded webs have the same arrangement as previouslydescribed in connection with FIGS. 1 to 3 inclusive. However, in thisinstance the folding edge or rod 9 is eliminated as is the guide 31. Thestructures of the folding boards are similar but the feeding of the webs41,42 involves laterally overlapping the webs.

Referring to FIG. 19, the first folding board 44 has a trapezoidalsurface 45, a depending rearward support 46, a forward dependingtrapezoidal surface 47 and a guide rod 48. Edges 50,51 laterally boundthe surface 45 and edges 52,53 bound the surface 47 laterally. Thenumeral 55 designates the lower left hand corner of surface 47 (FIG. 19)and the line of juncture of surfaces 45,47 is indicated by the numeral56.

The second folding board (FIG. 19) is generally indicated by the numeral57. It includes downwardly depending panel 58 having upper extension 59and lower lip 60 or fold line 60. Lip 60 has guide rod 61 securedthereto and the rod extends toward panel 62, above horizontally disposedpanel 63 and across the line of web travel indicated by the arrow (FIG.19). Panel 63 includes aperture 64 for receiving a retaining bolt or thelike for securing the folding board to a frame (not shown). Opening 65of panel 68 provides for web passage to the guide rod 61. The panels 58,62 and 63 may be formed, like board 17, from one piece of metal. Thebend line 68 indicates the juncture of panels 58 and 62, the juncture ofpanels 62 and 63 not being shown.

In this instance the folding of web 41 is much like that of the web 1 ofFIG. 1 in that the web 41 passed over surface 45 and its left edge (FIG.19) is drawn downwardly inwardly over edge 50 of the board 44. This leftedge is then guided by guided rod 48 inwardly beneath the opposite edgeof the web. The second web 42 (FIG. 19) overlies web 41 in much the samemanner that web 2 overlies partially folded web 1 in FIG. 14. The twowebs are then presented to the second folding board 57 in the samemanner as webs 1,2 were presented in FIGS. 15 through 18.

The interfolded webs, as illustrated in FIGS. 20 and 21, are of the sameconfiguration as the interfolded webs 1,2. These webs are intended, asalready indicated, as the upper webs of a stack and such a stack isillustrated in FIG. 22. Therein uppermost web 41 is indicated to havelongitudinal quarter folds in overlying relation and such that the web41 has an opening toward a side of the stack. This uppermost web is alsoclosed along a longitudinal zone intermediate the opposite side edges ofthe stack so that the complete web 41 is readily grasped on thelongitudinal center line rather than separate folds of the web. The web42 is interfolded with web 41, as already described, and with other webs70 having conventional folds 71,72 and webs 73 having folds 74,75.

The stacked webs are conventionally cut to length and provided inconsumer size cartons in generally known manner. The webs may beprovided in the carton in the rectangular arrangement shown in FIG. 22.Alternatively, the arrangement may be as indicated in fragmentary viewin FIG. 23, and a fragment of a carton designated at 76 has an ovalshaped perforation 37 for the purpose of providing an opening to thestacked tissues 38. In FIG. 23 only the upper webs are shown, and thestacked tissues are in a U shape. The start of the withdrawal is readilyaccomplished without damage to the individual webs.

In either method of production the resultant webs in the presentinstance have a stack of folded sheet material webs in which theuppermost web has longitudinal quarter folds, for example, la, 1b, 1c,1d (FIG. 2), in overlying relation. In the stack the arrangement is suchthat the uppermost folded web has an opening between folds 1b and 10toward the edge of the stack. This uppermost web 1 is closedintermediate the stack side edges along a longitudinal zone so that allfour folds of the upper web may be conveniently grasped. The next lowerweb has a pair of folds 2,2b which lie in the opening of the folds ofthe upper web and is partially withdrawn by withdrawal of the upperfold.

The term longitudinal as employed herein and the appended claims isintended to indicate the direction in which the web extends as it isfolded but is not intended to be limited to a particular length, thatis, cut length or otherwise.

As many apparently widely different embodiments of this invention may bemade without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myself to the specific embodimentsthereof except as defined in the appended claims.

What is claimed is:

l. A sheet material assembly comprising a stack of longitudinally foldedsheet material webs including an uppermost starter web and a next lowerweb, said uppermost web having longitudinal quarter folds all inoverlying relation providing a folded web having an opening toward aside edge of the stack, said next lower web having a fold lying in thesaid opening of the uppermost web so that withdrawal of the uppermostweb posed between the folds of the said central portion and the folds ofthe opposite edges.

3. A sheet material assembly according to claim 2 in which the said nextlower web has a pair of folds in contact which folds are the portion ofthe next lower web interposed between the folds of the central portionand the folds of the opposite edges of the uppermost web.

1. A sheet material assembly comprising a stack of longitudinally foldedsheet material webs including an uppermost starter web and a next lowerweb, said uppermost web having longitudinal quarter folds all inoverlying relation providing a folded web having an opening toward aside edge of the stack, said next lower web having a fold lying in thesaid opening of the uppermost web so that withdrawal of the uppermostweb from the stack also partially withdraws the said next lower web,said uppermost web being closed along a longitudinal zone intermediateside edges of the stack to permit grasping of the folded thickness ofthe said uppermost web.
 2. A sheet material assembly according to claim1 in which the quarter folds of the central portion of the uppermost weblie in contact, the quarter folds of the opposite edges of the uppermostweb lie in contact and the next lower web is interposed between thefolds of the said central portion and the folds of the opposite edges.3. A sheet material assembly according to claim 2 in which the said nextlower web has a pair of folds in contact which folds are the portion ofthe next lower web interposed between the folds of the central portionand the folds of the opposite edges of the uppermost web.